Drill-hole-enlarging device.



ANo. 796,165.'

PATBNTED AUG l, 1905.

T. M. TOPP. DRILL HOLE ENLARGING DEVICE,

APPLICATION'FILED MAY 1, 1905:v

THOMASV M. TOPP, OF RAYMOND, CALIFORNIA.

DmLL-HoLE-ENLARGING DEVICE.

Specication of Letters Patent.

Patented Aug; 1, 1905.

Application filed May l, 1905- Serial No. 258.352.

To a/ZZ whom t may concern:

Be it known that I, THOMAS M. TOPP, a citizen of the United States, residing at Raymond, in the county of Madera and State of Oalifornia, have invented new and useful Improvements in `Drill-Hole-Enlanging 'Devices of which the following is a specification.

My invention relates to a device which is designed for enlarging the bottom of drillholes and for like purposes.

It consists in the combination of parts and details of construction, which will be more fully explained by reference to the accompanying drawings, in which- Figure 1 is an elevation of my device assembled. Fig. 2 is an elevation of cutters and head. Fig. 3 is an elevation of elastic guide, partly in section. Fig. i is a section on line X X of Fig. 3. Fig. 5 is a section on line Y Y of-Fig. 3. Fig. 6 is a side elevation of plug.

It is the object of my invention to provide a means by which after drill-holes have been made in rock or other material the bottom of such holes may be enlarged and aehamber formed for the reception of the explosive with which the drill-hole is to be subsequently charged. It may also be employed for enlarging similar holes for other purposes.

As here shown, my device consists of five pieces, the head or shank A slightly-enlarged at the lower end, as shown at 2, and having a segmental opening 2 made transversely across this enlarged portion. The segment is greater than a semicircle for the purpose` of receiving and retaining the heads of the bits.

The cutting-bits 3 are diverged outwardly from the shank 3, and the heads or opposite ends of these shanks have a segmental shape, as shown at 4, so that when placed together they can be slipped into the segmental slot 2a. The inner faces of oneof these heads has a socket portion, as at 5, and the other has a corresponding projection, as at 6. From the socket 5 and part 6 the inner faces and upper portion of the heads 4. diverge outwardly, as shown at 7 so that if the Shanks 3a be laid parallel and close together the bits 3 will stand outwardly toward opposite sides. The projection 6 will fit into the projection 5 and prevent the bits from slipping in either direcl tion with relation to each other.

The divergent space caused by the beveling outwardly ofthe two faces 7 will allow the lower ends and thebits 3 to be separated,

while the heads I are turnable within the retaining-socket 2a, and as this socket is greater than a half-circle the lower ends approach each other sufficiently toretain the headst in place and prevent them from dropping out when suspended Yfrom the shank A.

-8 is an elastic guide, here shown as formed with sides sufficiently separated to receive the head 2 of the part A and the bits, and when these parts are ,assembled the sides of the guide 8 prevent the heads 4 from slipping out of the socket 2a. It will be seen that when thus assembled the parts while being loosely connected are prevented from dropping out or becoming dissociated. The bottom of the arms 8 are connected, and it is designed to rest in the bottom of the drill-hole. 9 is a small steel plug supported upon the bottom of the guides A and having the upper end convergent or beveled, as shown at 9.

The lower ends of the shanks 3a of the bits and between the bits are curved or diverged outwardly, as shown at 3b, so that when the bits are dropped within the guide 8 these divergent lower ends striking the convergent part 9a of the plug 9 will immediately separate the bits, thus driving their outer edges forcibly against the wall of the hole which is to be enlarged. The parts being thus assembled and the guide 3 being held against the bottom of the hole, the reciprocation of the head 2 and the forcible blows applied through it to the bits 3 will cause the latter to cut away the rock or material in which they operate until the hole is enlarged to the desired size.

It will be understood that the device may be used in connection with hand or machine drills and turned 4in the usual manner for drilling ordinary holes. By this construction all the parts are loosely fitted together. The device may be easily assembled or dismounted without the use of screws or bolts or implements of any kind.

Having thus described my invention, what I claim, and-desire to secure by Letters Patent. is-

1. A device for enlarging and chambering drill-holes, said device including shanks having outwardly-turned bits at one end, segmental heads at the opposite end about which they are turnable, said heads having divergent adjacent faces and an interlocking point and socket substantially central of the curvature of theheads,ashankhavingatransverselydisposed segmental channel within which said heads fit and are turnable, and a fixed wedgeshaped block whereby the bits are forcibly separated at each stroke or impulse.

2.111 a device for enlarging and chambering drill-holes, Shanks having outwardlyturned bits at the lower end, segmental heads at the opposite end, said heads having divergent adjacent faces and an interlocking point and socket substantially central of the curvature of the heads, a shank having a transverse segmental channel within which the heads of the drill-Shanks are suspended. a guide within which these parts are reciprocable, and a fixed wedge-shaped block at the lower end against which the contiguous faces of the bits are impelled and the bits forced outwardly.

3. In a drill-hole enlarging and chambering device Shanks having outwardly-turned bits at one end, segmental heads at the opposite end with divergent adjacent faces and an interlocking point and socket substantially central of the curvature of the heads, a shank having a transverse segmental chamber in which said heads are fitted and movable to allow the bits to be separated, a guide within which the shanks and bits are contained and a fixed wedge-shaped block at the lower end of the guide against which the bits are impelled, and by which they are forcibly7 separated at each impulse.

In testimony whereof l have hereunto set my hand in presence of two subscribing witnesses.

THOMAS M. TOPP. Witnesses:

WM. S. VAN DALsuM, L. P. HANNAFARD. 

